American Journal of Environmental Protection 2014; 3(5): 232-237 Published online October 30, 2014 (http://www.sciencepublishinggroup.com/j/ajep) doi: 10.11648/j.ajep.20140305.14 ISSN: 2328-5680 (Print); ISSN: 2328-5699 (Online)
Water quality assessment of an industrial zone polluted aquatic body in Dhaka, Bangladesh Mahmuda Akter1, *, Tajuddin Sikder1, 2, A. K. M. Atique Ullah3 1
Department of Environmental Science, Stamford University Bangladesh, Dhaka-1209, Bangladesh Department of Public Health, Jahangirnagar University, Dhaka-1342, Bangladesh 3 Chemistry Division, Atomic Energy Centre Dhaka, Bangladesh Atomic Energy Commission, Dhaka-1000, Bangladesh 2
Email address:
[email protected] (M. Akter)
To cite this article: Mahmuda Akter, Tajuddin Sikder, A. K. M. Atique Ullah. Water Quality Assessment of an Industrial Zone Polluted Aquatic Body in Dhaka, Bangladesh. American Journal of Environmental Protection. Vol. 3, No. 5, 2014, pp. 232-237. doi: 10.11648/j.ajep.20140305.14
Abstract: Water quality in the aquatic body of Dhaka Export Processing Zone (DEPZ) area was studied on the basis of some physiochemical parameters and heavy metal concentrations. Physiochemical parameters like pH, Electrical Conductivity (EC), Chemical Oxygen Demand (COD), Total Dissolved Solids (TDS) and concentrations of some heavy metals like As, Cd, Cu, Co, Cr, Fe, Mn, Ni, Pb, Hg and Zn were measured. Among different physiochemical parameters, pH, TDS and EC were found within the range. The range of pH for all of the samples was found from 7.1 to 8.17 and 120 to 450 mg/L for TDS. The Values of EC were found from 90 to 300 µs cm-1. For pH, EC and TDS, though the ranges were within the limits but there was an increasing trend of the values was observed in every case which is highly alarming. The range of COD values was estimated from 90 to 300 mg/L and in most of the samples the values exceeded the standard range. The heavy metal containments of the surface water indicated that the concentrations of Cr, Cu, Ni, Zn, Hg and As were obtained below the permissible limit, detection by WHO, 1996. On the other hand, concentrations of Cd, Co, Fe, Pb, Mn and Hg were exceeded the permissible limits. Correlation matrix shows a significant correlation among Pb, Cu, Co, Mn and Fe. Enrichment factor shows high concentrations of Cd, Cr and Hg. Stated environmental condition is highly vulnerable for human being, that’s why this is the time to take proper steps for remediation and preventing the pollution around DEPZ water body which is directly related to the industrial emission of DEPZ. Keywords: Water Quality, Physiochemical Parameter, Heavy Metal, DEPZ
1. Introduction Pollution, nowadays, has become a serious concern for human life due to the industrial burst in the world. And, the rivers are the main choices to hold and bear the responsibility of pollutants, especially in the developing countries. Water pollution caused by chemical substances such as heavy metals affects tropical rain forest and river ecology. Heavy metals can accumulate from water to sediments through settling process and some particles can also find their ways into the biota [1]. Bangladesh is said to be the land of rivers [2]. Increasing industrialization and unplanned urbanization have greatly transformed the natural environment, particularly water sector or natural hydrological system of Bangladesh. The concerns over surface water quality are gradually emerging due to the disposed location of industrial units and
the adverse effects on surrounding land and aquatic environment, as well as subsequent impacts on the livelihood system of the local community [3]. Dhaka Export Processing Zone (DEPZ) being the 2nd EPZ of Bangladesh has started its operation in 1993 and at present houses 92 industrial units which are categorically the leading pollution creators. These industrial units in number are as follows: cap/accessories/garments (42); textile/knitting (22); plastic goods (6); footwear/leather goods (4); metal products (2); electronic goods (2); paper products (1); chemical and fertilizer (1) and miscellaneous (11) [2]. Every industrial unit is supposed to have Effluent Treatment Plant (ETP) to treat the respective wastewater they generate. However, so far only a few industries have installed such plants. Even then most of the installed ETPs operate occasionally only to be qualified to international buyers and to get clearance certificate from Department of Environment
American Journal of Environmental Protection 2014; 3(5): 232-237
(DoE) [4.]. Most of the industries discharge their effluents containing heavy metals without any prior treatment through open drain and contaminates water, soil and vegetables of the adjacent areas. Pollution from the DEPZ has already affected the wetland and some of the streams ruining aquatic habitats and natural fisheries. Recently, it has been reported that the surface water body connected to DEPZ effluent disposal sites have been steadily contaminated with a huge number of heavy and toxic metals [5]. Therefore, it is an urgent need to figure out the present status of toxic heavy metals in this water body, redress environmental problems and adopt future mitigation strategy [6]. The aim of this work was to investigate the general water quality of the DEPZ adjacent water body. In this purpose we estimated some physiochemical parameters as well as heavy metals (Fe, As, Mn, Co, Cu, Ni, Pb, Zn, Hg, Cr and Cd) concentrations. This research will provide a clear idea about the present water quality of DEPZ adjacent area which will be a basis of future research and monitoring activities for preventing water pollution around the DEPZ area and the data generated in this work may help to work out in effluent management strategy towards control over effective treatment of the DEPZ discharges in terms of toxic and heavy metal contents.
2. Materials and Methods 2.1. Study Area and Sampling
Fig 1. Map of the study area showing the sampling points.
DEPZ adjacent lake water was the study area which is in Dhamsona Union, under Savar Upazila of Dhaka District. It is about 35 Kms from Dhaka city and 25 kms from Hazrat Shahjalal (R.) airport [7]. The area is blazed with numerous industries. There are two export processing zones (old and new) are in service within this girdle. Between these two EPZs the national highway from northern Bangladesh to
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Dhaka is running. The present study was carried out in September 2013. All of the samples were collected from the DEPZ adjacent lake water in 230 57/ N to 900 15/ E and are shown in Fig. 1. For the determination of physiochemical parameters and heavy metal concentrations samples were collected from ten different points in west bill of DEPZ. Samples were collected in 1L polyethylene bottles. At first sampling bottles were preconditioned with 5% nitric acid (HNO3) and later rinsed thoroughly with de-ionized water for three times, finally they were dried. At each sampling site, the polyethylene sampling bottles were rinsed with sampling water (water collected for analysis). About 1L of ten surface water samples were collected from ten different places. These places were adjacent areas of DEPZ. The pre-cleaned polyethylene bottles were dipped about 9-10 cm below the surface of the lake. After collecting the samples the bottles were sealed carefully. The sampling bottles were marked by a permanent marker pen for remarking the sample number and sample location. Then the sampling bottles were transferred to the laboratory for further analysis as early as possible. The water samples were filtered using 41 Whatman filter paper. About 500 mL of each of the filtered were preserved with ultra pure nitric acid to bring down the pH to
